Block hours are paid in the month you fly them. Credit time on a carry over trip is paid the next month.
I have a 7 day DKR/ABV I start on March 25. It pays 15 hours in March and 30 hours in April.
I also have 9:45 credit in April for recurrent (lucky me)
For April the 7ER B ALV is 75:00.
Since I already have 39:48 in credit , I must bid between 27:42 and 42:42 for PBS to build me a line.